| Number of studies | Number of participants (%) | Mean | SD |
---|---|---|---|---|
Sample size | 18 | 1,24,554 | Â | Â |
Age | 18 | Â | 15 | 3.32 |
Sex | Â | Â | Â | Â |
Male | 18 | 62,572 (50.2) | Â | Â |
Female | 18 | 61,982 (49.8) | Â | Â |
Geographic location | Â | Â | Â | Â |
America | 6 | 39,057 (31.4) | Â | Â |
Europe | 6 | 37,665 (30.2) | Â | Â |
Asia | 5 | 47,236 (37.9) | Â | Â |
Oceania | 1 | 596 (0.5) | Â | Â |
Study design | Â | Â | Â | Â |
Cross-sectional | 16 | 1,14,270 (91.7) | Â | Â |
Prospective cohort | 2 | 10,284 (8.3) | Â | Â |
Study setting | Â | Â | Â | Â |
School | 13 | 92,145 (74.0) | Â | Â |
Others a | 5 | 32,409 (26.0) | Â | Â |
Instrument | Â | Â | Â | Â |
Self-designed | 4 | 58,261 (46.8) | Â | Â |
Others b (standardized) | 14 | 66,293 (53.2) | Â | Â |
Method of assessment | Â | Â | Â | Â |
Self-report | 15 | 1,00,539 (80.7) | Â | Â |
Face-to-face interview | 3 | 24,015 (19.3) | Â | Â |
Substance use | 18 | 55,936 (44.9) | Â | Â |
Alcohol | 15 | 20,953 (37.5) | Â | Â |
Smoking | 15 | 25,626 (45.8) | Â | Â |
Coffee | 3 | 64,66 (11.5) | Â | Â |
Marijuana | 3 | 2891 (5.2) | Â | Â |
Sleep disturbance | Â | Â | Â | Â |
Insomnia | 12 | 9057 (16.2) | Â | Â |
Hypersomnolence | 4 | 1625 (2.9) | Â | Â |
SRBD | 3 | 5167 (9.2) | Â | Â |